To: <topband@contesting.com>
> Date: Wed, 30 Jul 97 13:46:32 +0000
> I am surprised by the analysis that adding radials at the antenna has such a
> major effect on the angle of radiation. This would seem to mean that if you
> sit in the middle of a 250 ft diameter salt water pond, it does not matter
> what the ground conductivity is several wavelengths from the antenna.
>
> 73 de VE7BS
You should be surprised Bob.
A vertical antenna's radiation angle is affected very little by a
near field radial system. The only exception would be if the radials
were actually radiating.
Contrary to Hamlore, adding radials does not noticeably change the
radiation angle of a vertical. All it does is change the OVERALL
pattern size, by reducing nearfield loss.
Now if you add 5 wl long radials, and keep the far ends less than .05
wl apart by using enough radials, it would change the elevation
pattern a useful amount. ;-)
73, Tom W8JI
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